Improvement in packings for balanced piston-valves



D. DALE.

PACKING'FOR BALANCED PISTON VALVES.

No.178,604, Patented June 13, 1876.

MTNESSES: "N208 I N.PETERS. PNDTO LITHOGRAFHEE WASMXNGTON. D C.

UNITED STATES DAVID DALE, OF MILLERSTOWN, PENNSYLVANIA.

IMPROVEMENT IN PACKINGS FOR BALANCED PISTON-VALVES.

Specification forming part of Letters Patent No. 178,604, dated June13,- 1876; application filed 1 April 25, 1876.

To all whom it may concern Be it known that 1, DAVID DALE, ofMillerstown, in the county of Butler and State of Pennsylvania, haveinvented a new and Improved Balanced Piston-Valve, of which thefollowing is a specification My invention relates to the employment ofsteam for pressing out the packings of the piston, alsoto thearrangement of the pistons and followers relatively to the live-steamchamber. The first part, consists of a contrivance of radial plugs inthe pistons, on which steam is caused to act to push out thepackingring, one of the said plugs acting by a wedge between the ends ofthe ring to expand it, and another, or more if desired, acting by astifi spring, which bears at its ends on the packingring and distributesthe pressure upon two points.

Figure l is a longitudinal sectional elevation of one of the heads,taken on line 00 0c of Fig. 2, and side elevation of the other. Fig. 2is an end elevation of one of the pistons with the follower removed; andFig. 3 is a transverse section ot' the shaft, taken on line 3 y, Fig. 1.

A represents the piston-heads, which are fitted on the rod B, and have ahub, G, on the steam side. D is the packing-ring, and E the follower. Atthe side of the piston where the ends of the packing-ring meet is awedge, F, for expanding the ring by pressure behind it.

p This wedge has a stud, G, on the back, enter ing a socket in the plugH, which" bears at its outer end against the back of the wedge. Thesocket is a little larger than the stud, to allow the wedge freedom toadjust itself to the space between the ends of the ring. Steam is let inagainst the inner end of the plug by the inletpassage I fromthe'live-steam space. On the opposite side is a plug, J, similarlypressed out bysteam let in behind it by anotherinlet, 1. This plug bearsagainst a spring, K, which, at its ends, bears against the packing-ring,to assist the wedge in tightening the packing,

. and to distribute the pressure. Two or three of these plugs J may beemployed in case it may be desired to distribute the pressure stillmore. M is a small hole through the follower for the escape of any steamthat may leak past the packing to the inside.

The hub O is to strengthen the connection of the'piston with the rod andstiffen the latter, the same being located on the steam side, whichenables the follower to be located on the outside for greaterconvenience, and to avoid the leaking of steam through the boltholes.

Having thus described my invention, whatI claim as new, and desire tosecure by Letters Patent, is-

1. The combination of the wedge F and plug H with the packing D and thepiston, the latter having an inlet-passage, I, to the plug for livesteam, substantially as specified.

2. The combination of the spring K and plug J with the packing-ring D,piston A, and the plug H and wedge F, substantially as specified.

' DAVID DALE.

Witnesses:

Z. NEWELL, P. O. NEVIL.

PATENT Frin-

